Health

Diet and DNA: The mysterious link between genes and eating habits

Have you ever asked yourself, why am I not losing any weight despite exercising so hard? The answer might actually lie in your genes. - Filepic

The field of nutrigenomics may reveal the answers to the mysterious link between our genes and our eating habits.

In this age of information, we are constantly bombarded with a barrage of do’s and don’ts on healthy eating and losing weight, each promising you easier and quicker weight-loss and wellness solutions.

We continue looking for the ultimate diet solution – one that can magically dissolve fat and reduce weight while we continue chomping on all our favourite foods.

While science may not have stumbled upon that magic solution just yet, it has certainly made some groundbreaking strides in the study of genetics and how they can influence our eating habits.

It appears that the answers to questions like: “Why am I exercising, but not losing weight?”, “Why do I put on weight when I hardly eat?”, and “Why has my friend lost more weight than I have on the same diet plan?”, could all be contained inside our own DNA.

It’s in the genes

According to experts, our genes, or DNA, may now reveal why we may be naturally predisposed to weight gain, have a low metabolism, cannot process or store sugar effectively, or are unable to discard toxins from our bodies.

The science of nutrition and dietetics have joined forces with genomics (the study of genes) in a field known as nutrigenomics, which sheds some light on how and why different people react to certain foods or nutrients.

“Nutrigenomics is an emerging discipline that explores the benefits of food on the individual.

“It identifies the different genetic makeup of each individual, and which type of food is suitable for the individual according to their genetic makeup; basically, it is how food talks to our genes.

“Understanding this can help to bring out the greatest potential in our genes,” explains Kuala Lumpur Sports Medicine Centre primary care and family physician Dr Surinder Kaur Gill.

Dr Surinder... Nutrigenomics helps us identify the genes that are working in your favour, and more importantly, those that are working against you. - Kuala Lumpur Sports Medicine Centre

According to Dr Surinder, nutrigenomics removes the guesswork from healthy eating as it identifies exactly what type of nutrients everybody needs, or does not need.

“Most of us today take many supplements because of what we read and discuss with our friends, because we think our body is lacking nutrients and therefore, we need to replenish them.

“In actual fact, it is more important to determine if we lack any nutrients at all, and if so, which nutrient and how much is lacking.

“This is one of the major roles that nutri-genomics can play in healthcare today; in simple terms, it’s like how we decide to buy clothes based on our body type, shape and size,” she says.

The process begins with a genetic profile, where the individual’s genes are mapped out, to better understand how their genes can affect their health and wellbeing.

This genetic profile is performed from a tissue sample obtained from the buccal mucosa (the inside of your cheek) by taking a simple, painless swab.

Dr Surinder explains: “The initial consultation begins with a detailed interview and history-taking, which involves the patient’s medical and family history as far back as three generations.

“Following that, the genetic profiling and specific blood tests are performed to enable us to determine the genes that are working in your favour, and more importantly, the genes that are working against you.

“With this information, we can recommend appropriate lifestyle and dietary actions in order to activate and deactivate the genes accordingly.”

As nutrigenomics continues to advance, healthcare professionals will be able to tailor dietetic advice to each individual, based on his or her genetic profile.

This form of personalised medicine is the direction that the healthcare industry worldwide is moving towards.

A weapon
against obesity

Perhaps one of the key breakthroughs of nutrigenomics is its ability to help determine an individual’s predisposition to certain non-communicable diseases (NCDs) like obesity, cancer, heart disease and diabetes.

This would be especially useful as Malaysia continues to see an alarming increase in obesity and diabetes.

Our country is currently ranked sixth in Asia Pacific for obesity, and tops the list in South-East Asia for both obesity and diabetes – making NCDs a critical area of concern for local healthcare professionals.

“Reduced physical activity in daily life and increased availability of cheap calorie-dense food are the main culprits of the obesity epidemic.

“However, we have noticed that the environment is not the only contributing factor. Studies have increasingly shown that genetic makeup may be more important than the environment.

“This explains why some people become obese and others don’t, even when exposed to a similar environment,” explains Dr Surinder.

Nutrigenomics attempts to identify the genetic variations that can help us understand differing eating patterns, fat metabolism and responses to exercise, which are all linked to our genetic make-up.

These differences explain why some people may put on weight despite not eating much, and others do not seem to gain any weight despite having huge appetites.

“What we have found out is that there’s a variation of genes in these people, where their stomach is unable to send a signal to the brain to indicate that they are full.

“For example, I had a patient, a 45-year-old male who used to eat 20 roti canai for breakfast every day and never felt full!

“Despite exercising daily and skipping his other meals, this patient kept putting on weight.

“Not surprisingly, he also had a host of other health problems, such as high blood sugar, high cholesterol and high blood pressure.

“The genetic profiling revealed that he carried the ‘variation gene’. So, I advised the appropriate lifestyle changes according to his gene variation,” shares Dr Surinder.

She adds that in just six months, the patient managed to shed almost 30kg, going from 120kg to 93kg. He was also able to go off his medication and felt much healthier as a result.

These breakthroughs open up a new horizon for preventive medicine, as it enables healthcare professionals to increase the quality of life and living, given rising life expectancy rates.

“People are living quite long these days, but we find that the ‘dying process’ is also very long.

“In other words, many older or elderly people don’t have good quality of life because they are ill or bedridden.

“We can’t add on the number of years to a person’s life, but we can improve the quality of life to ensure that patients live independently for as long as possible,” says Dr Surinder.

> This article was provided by the Kuala Lumpur Sports Medicine Centre.